Zyyini Liquid Level Sensor,4-20MA Level Transmitter 304 Stainless Steel 5 Meters Liquid Level Sensor Input Type

This sensor is sold under various brands by various firms. (The photo is identical on all offerings here on Amazon.) These are connected to a PLC measuring tank levels ranging from 8 to 26 feet in depth. We dropped them in the tank, filled them, then entered the empty and full readings as our scale. We now have fairly accurate depth measurements for each tank.These units replaced FlowLine EchoPod Ultrasonic sensors that cost ten times the price. The EchoPods continued to throw false readings (empty or full) at apparently random times during the day. These have been solid.The one page of instructions is in Chinese. However, the only item of interest is the photo showing the plus and negative wire. Any electronics tech will understand the obvious way to connect it.

I bought a couple of these just to try because my regular supplier of level transducers was out of stock. I have been paying $350 for a good transducer but this one is only $65 so for that price I expect some difference. It has no atmospheric vent to compensate for outside pressure and it is about 5% less sensitive to pressure changes. IT also was reading 4.50 MA went not under pressure so it reads a little high out of the box, it should read 4.00 MA in the air. I have only had it in service for a few days so I will update if things change

I took a chance as this pressure sensor has a much wider range than what I need. Really I needed a 0-1.5psi for my black tank. With that being said, at empty the tank still shows about 10% instead of empty. It does seem to be accurate enough as the tank starts to fill up. And the top of my tank (~20") seems spot on. For 1/4 of the price of the 0-1.5psi sensor I'm very happy with it.